For manufacturing electronic components such as semiconductor devices, a magnetically enhanced spatter apparatus is widely used. Conventionally, it is known that a magnet apparatus having various magnet arrangements is disposed on the back side of a target in accordance with purposes such as generating a plasma, confining a plasma, increasing a plasma density, and improving uniformity of film formation (Non Patent Document 1 and Patent Document 1).
Furthermore, in Patent Document 1, a technique is disclosed in which variation of sputtering speed over time is suppressed by adjusting a distance between the magnet apparatus and the target in accordance with variation of a magnetic field on the surface of the target due to erosion (corrosion) of the target member.